xref: /freebsd/libexec/tftpd/tftpd.8 (revision 1130b656e5fe4c2d1ba299e024d1b40eaeebd380)
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32.\"	@(#)tftpd.8	8.1 (Berkeley) 6/4/93
33.\"
34.Dd June 4, 1993
35.Dt TFTPD 8
36.Os BSD 4.2
37.Sh NAME
38.Nm tftpd
39.Nd
40Internet Trivial File Transfer Protocol server
41.Sh SYNOPSIS
42.Nm tftpd
43.Op Fl l
44.Op Fl n
45.Op Fl s Ar directory
46.Op Ar directory ...
47.Sh DESCRIPTION
48.Nm Tftpd
49is a server which supports the
50Internet Trivial File Transfer
51Protocol (\c
52.Tn RFC 783).
53The
54.Tn TFTP
55server operates
56at the port indicated in the
57.Ql tftp
58service description;
59see
60.Xr services 5 .
61The server is normally started by
62.Xr inetd 8 .
63.Pp
64The use of
65.Xr tftp 1
66does not require an account or password on the remote system.
67Due to the lack of authentication information,
68.Nm tftpd
69will allow only publicly readable files to be
70accessed.
71Files containing the string ``/\|\fB.\|.\fP\|/'' are not allowed.
72Files may be written only if they already exist and are publicly writable.
73Note that this extends the concept of
74.Dq public
75to include
76all users on all hosts that can be reached through the network;
77this may not be appropriate on all systems, and its implications
78should be considered before enabling tftp service.
79The server should have the user ID with the lowest possible privilege.
80.Pp
81Access to files may be restricted by invoking
82.Nm tftpd
83with a list of directories by including up to 20 pathnames
84as server program arguments in
85.Pa /etc/inetd.conf .
86In this case access is restricted to files whose
87names are prefixed by the one of the given directories.
88The given directories are also treated as a search path for
89relative filename requests.
90.Pp
91The chroot option provides additional security by restricting access
92of tftpd to only a chroot'd file system.  This is useful when moving
93from an OS that supported
94.Nm -s
95as a boot server.  Because chroot is restricted to root, you must run
96tftpd as root.  However, if you chroot, then
97.Nm tftpd
98will set its user id to nobody.
99.Pp
100The options are:
101.Bl -tag -width Ds
102.It Fl l
103Logs all requests using
104.Xr syslog 3 .
105.It Fl n
106Suppresses negative acknowledgement of requests for nonexistent
107relative filenames.
108.It Fl s Ar directory
109Causes tftpd to chroot to
110.Pa directory
111before accepting commands.  In addition, the user id is set to
112nobody.
113.El
114.Sh SEE ALSO
115.Xr tftp 1 ,
116.Xr inetd 8
117.Sh HISTORY
118The
119.Nm
120command appeared in
121.Bx 4.2 .
122